ES2911491T3 - (Meth)acrylic block copolymer and active energy ray curable composition containing it - Google Patents

Abstract

An active energy ray curable composition, comprising a (meth)acrylic block copolymer comprising a methacrylic polymer block (A) having an active energy ray curable group including a partial structure (1) represented by general formula (1) below, and a block (B) of an acrylic polymer having no groups curable by active energy rays; **(See formula)** where R1 indicates a hydrocarbon group having from 1 to 10 carbon atoms, and W indicates a saturated hydrocarbon group having from 1 to 10 carbon atoms, where the polymer block (A) methacrylic having the active energy ray curable group including a partial structure (1) includes monomer units which are derived from a methacrylate ester represented by the general formula (2) below; **(See formula)** where R1 and W are as defined hereinabove.

Description

DESCRIPTION

(Meth)acrylic block copolymer and active energy ray curable composition containing it

The present invention relates to an active energy ray curable composition containing a (meth)acrylic block copolymer having a specific active energy ray curable group.

Active energy ray curable compositions are conventionally known which cure when irradiated by active energy rays such as UV lights or electron beams. Such curable compositions are used in applications including adhesives, pressure sensitive adhesives, paints, inks, coating materials, and stereolithographic materials.

On the other hand, (meth)acrylic block copolymers including a methacrylic polymer block and an acrylic polymer block have excellent properties such as adhesion, conformability and weather resistance. These features are expected to expand the use of the copolymers into applications such as pressure-sensitive adhesives, adhesives, coating materials, and various forming materials. Furthermore, the combined properties of the above material types are exhibited in (meth)acrylic block copolymers that include a methacrylic polymer block and an acrylic polymer block and have an active energy ray curable functional group that is activated by active energy ray irradiation or activated by a photoinitiator activated by such irradiation (hereinafter, such functional group is referred to as "active energy ray curable group") (see Patent Document 1). For example, such (meth)acrylic block copolymers can be obtained by forming an acrylic polymer block by polymerizing butyl acrylate and copolymerizing methyl methacrylate and allyl methacrylate to introduce allyl groups which serve as active energy ray curable groups.

Patent Document 1: JP-A-2011 -184678

One challenge facing active energy ray curable compositions is improving the speed of cure when the compositions are irradiated with active energy rays. The curing rate depends on the structure of the active energy beam curable groups. Of the active energy ray curable groups, allyl groups are known to have relatively low reactivity. In particular, such groups, when present in acrylate monomer compositions used in various applications such as adhesives, pressure sensitive adhesives, paints, inks, and coating materials, show a remarkably low cure rate. The present invention has been made based on the circumstances discussed above. Therefore, it is an object of the present invention to provide an active energy ray curable composition containing a (meth)acrylic block copolymer exhibiting excellent active energy ray curing ability.

The present inventors conducted extensive studies aimed at solving the problems described above. As a result, the present inventors have found that a (meth)acrylic block copolymer having a specific active energy ray curable group exhibits good curability, and have completed the present invention based on that finding and further studies.

That is, the present invention relates to:

[1] An active energy ray curable composition comprising a (meth)acrylic block copolymer including a methacrylic polymer block (A) having an active energy ray curable group including a partial structure (1) shown by the general formula (1) below, and an acrylic polymer block (B) having no active energy ray curable groups;

where R1 indicates a hydrocarbon group having from 1 to 10 carbon atoms, and W indicates a saturated hydrocarbon group having from 1 to 10 carbon atoms, where

the methacrylic polymer block (A), having the active energy ray curable group including a partial structure (1), includes monomer units which are derived from a methacrylate ester represented by the general formula (2) below ;

where R1 and W are as defined hereinbefore.

[2] The composition curable by active energy rays described in [1], where the ratio of the number of moles of the partial structures (1) with respect to the number of moles of all the monomeric units that constitute the methacrylic polymer block (A) is 0.1 to 50 mol%.

The (meth)acrylic block copolymers described herein exhibit excellent active energy ray curability. The active energy beam curable compositions according to the present invention contain the (meth)acrylic block copolymers. Cured products of these materials are also provided.

The present invention will be described in detail below.

In the present specification, the term "(meth)acrylic" is a general term indicating both "methacrylic" and "acrylic".

A (meth)acrylic block copolymer described herein includes a methacrylic polymer block (A), which has an active energy ray curable group including a partial structure (1), and an acrylic polymer block (B) which does not It has groups curable by active energy rays.

Methacrylic polymer blocks (A)

The methacrylic polymer block (A) has an active energy ray curable group including a partial structure (1) represented by the following general formula (1).

[Who . two]

In the formula, R1 indicates a hydrocarbon group having 1 to 10 carbon atoms, and W indicates a saturated hydrocarbon group having 1 to 10 carbon atoms,

Active energy ray curable groups including a partial structure (1) exhibit polymerization ability when irradiated with active energy rays. As a result of this polymerization ability, the (meth)acrylic block copolymer described herein, or an active energy beam curable composition of the invention containing the copolymer, is cured into a cured product by the application of active energy beams. . In the present specification, the term "active energy rays" means light rays, electromagnetic waves, particle rays, and combinations thereof. Examples of light rays include far ultraviolet light, ultraviolet (UV) light, near ultraviolet light, visible light, and infrared light. Examples of electromagnetic waves include x-rays and y-rays. Examples of particle beams include electron beams (EB), proton beams (a-particle beams), and neutron beams. Of these active energy rays, ultraviolet lights and electron beams are preferable from viewpoints such as curing rate and availability and price of irradiators, with ultraviolet lights being more preferable.

In the general formula (1), R1 indicates a hydrocarbon group having 1 to 10 carbon atoms. Here, the hydrocarbon group represented by R1 is a monovalent hydrocarbon group having no double or triple bonds. Examples of the hydrocarbon groups with 1 to 10 carbon atoms indicated by R1 include, for example, alkyl groups such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group , t-butyl group, 2-methylbutyl group, 3-methylbutyl group, 2-ethylbutyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, n-pentyl group, neopentyl group, n-hexyl group, group 2 -methylpentyl, 3-methylpentyl group and ndecyl group; cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group and cyclohexyl group; aryl groups such as phenyl group and naphthyl group; and aralkyl groups such as benzyl group and phenylethyl group. From the viewpoint of active energy ray curability, R 1 is preferably a saturated hydrocarbon group having 1 to 6 carbon atoms, more preferably a saturated hydrocarbon group having 1 to 2 carbon atoms, and even more preferably a methyl group. Active energy ray curable groups including partial structure (1) exhibit higher reactivity and achieve higher cure capacity by beams of active energy probably as a result of R1 being an electron-donating hydrocarbon group, and not a hydrogen atom.

In the general formula (1), W indicates a saturated hydrocarbon group having 1 to 10 carbon atoms. Here, the saturated hydrocarbon group represented by W is a divalent hydrocarbon group having no double or triple bonds. W can be linear, branched, or cyclic, preferably linear or branched, and more preferably linear. Examples of W include ethane-1,1-diyl group, ethane-1,2-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-1 ,3-diyl, pentane-1,5-diyl group, hexane-1,6-diyl group and cyclohexane-1,4-diyl group. From the viewpoint of active energy ray curing ability, W is preferably a saturated hydrocarbon group having 2 to 6 carbon atoms, more preferably a saturated hydrocarbon group having 2 carbon atoms, and particularly preferably an ethane-1,2-diyl group.

From the viewpoint of active energy ray curability, the ratio of the number of moles of the partial structures (1) to the number of moles of all the monomer units constituting the methacrylic polymer block (A) is preferably in the range of not less than 0.1 mol% and not more than 50 mol%, more preferably in the range of not less than 0.5 mol% and not more than 40 mol%, and even more preferably in the range of not less than 1.0 mol% and not more than 30 mol%.

Active energy ray curable groups including partial structure (1) may be present at a terminal end or side chain of the methacrylic polymer block (A). In order to achieve a preferred proportion of the partial structures (1) that are introduced, it is preferable that the groups are present at least in side chains.

The methacrylic polymer block (A) includes monomer units which are derived from a methacrylate ester represented by the general formula (2) below. When a methacrylate ester represented by the general formula (2) is used, methacryloyl groups are selectively polymerized by living anionic polymerization, under conditions to be described later, to form a methacrylic polymer block (A) having a curable group by rays of active energy including a partial structure (1).

[Wh ím. 3]

In the formula, R1 indicates a hydrocarbon group having 1 to 10 carbon atoms, and W indicates a saturated hydrocarbon group having 1 to 10 carbon atoms.

Specific examples of the general formula (2) include 3-methyl-3-butenyl methacrylate, 4-methyl-4-pentenyl methacrylate, 5-methyl-5-hexenyl methacrylate, 6-methyl-6-heptenyl methacrylate , 7-methyl-7-octenyl methacrylate, 3-ethyl-3-butenyl methacrylate, 4-ethyl-4-pentenyl methacrylate, 5-ethyl-5-hexenyl methacrylate, 6-ethyl-6-heptenyl methacrylate and 7-ethyl-7-octenyl methacrylate. Of these, 3-methyl-3-butenyl methacrylate, 4-methyl-4-pentenyl methacrylate, 5-methyl-5-hexenyl methacrylate, 6-methyl-6-heptenyl methacrylate and 7-methyl methacrylate are preferable. methyl-7-octenyl, and 3-methyl-3-butenyl methacrylate is more preferable. The methacrylate esters can be used singly or two or more can be used in combination.

From the viewpoint of active energy ray curability, the ratio of the number of moles of monomeric units obtained from the methacrylate ester of general formula (2) to the number of moles of all monomeric units constituting the methacrylic polymer block (A) is preferably in the range of not less than 0.1 mol% and not more than 50 mol%, more preferably in the range of not less than 0.5 mol% and not more than 40 mol%, and even more preferably in the range of not less than 1.0 mol% and not more than 30 mol%.

In addition to the monomeric units of the methacrylate ester represented by the general formula (2), the methacrylic polymer block (A) preferably includes monomeric units derived from a monofunctional methacrylate ester having a methacryloyl group.

Examples of monofunctional methacrylate esters having a methacryloyl group include, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, cyclohexyl methacrylate , 2-ethylhexyl methacrylate, isobornyl methacrylate, dodecyl methacrylate, 2-methoxyethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxybutyl methacrylate, trimethoxysilylpropyl methacrylate, 2-aminoethyl methacrylate, N,N-dimethylaminoethyl methacrylate , N,N-Diethylaminoethyl Methacrylate, Phenyl Methacrylate, Naphthyl Methacrylate, Ethyl 2-(Trimethylsilyloxy)Methacrylate, 3-(Trimethylsilyloxy)propyl Methacrylate, Glycidyl Methacrylate, Y -(Methacryloyloxypropyl)trimethoxysilane, Oxide Adduct ethylene from Methacrylic acid, trifluoromethylmethyl methacrylate, 2-trifluoromethylethyl methacrylate, 2-perfluoroethyl methacrylate, 2-perfluoroethyl-2-perfluorobutylethyl methacrylate, 2-perfluoroethyl methacrylate, perfluoromethyl methacrylate, diperfluoromethylmethyl methacrylate, 2-perfluoromethyl-2 methacrylate -perfluoroethylmethyl, 2-perfluorohexylethyl methacrylate, 2-perfluorodecylethyl methacrylate and 2-perfluorohexadecyl methacrylate. Of these, alkyl methacrylates having an alkyl group with 1 to 5 carbon atoms, such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate and sodium methacrylate, are preferable. t-butyl. Methyl methacrylate is more preferable.

The content of the monomeric units obtained from the monofunctional methacrylate ester having a methacryloyl group (for example, methyl methacrylate) is preferably not less than 30% by mass with respect to all the monomeric units in the methacrylic polymer block ( A), and is more preferably not less than 40% by mass, and even more preferably not less than 50% by mass.

Furthermore, the ratio of the number of moles of the monomer units obtained from the monofunctional methacrylate ester having a methacryloyl group (for example, methyl methacrylate) is preferably in the range of not less than 50 mol% and not more than 99.9 mol%. and more preferably in the range of not less than 60 mol% and not more than 99.5 mol% with respect to the number of moles of all monomer units in the methacrylic polymeric block (A).

The methacrylic polymer block (A) may include monomeric units derived from an additional monomer other than methacrylate esters represented by the general formula (2) and monofunctional methacrylate esters having a methacryloyl group. Examples of such additional monomers include, for example, acrylate esters such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, cyclohexyl acrylate, 2-Ethylhexyl Acrylate, Isobornyl Acrylate, Dodecyl Acrylate, 2-Methoxyethyl Acrylate, 2-Hydroxyethyl Acrylate, 2-Hydroxybutyl Acrylate, Trimethoxysilylpropyl Acrylate, 2-Aminoethyl Acrylate, N,N-Dimethylaminoethyl Acrylate, N,N-diethylaminoethyl acrylate, phenyl acrylate, naphthyl acrylate, 2-(trimethylsilyloxy)ethyl acrylate, 3-(trimethylsilyloxy)propyl acrylate, glycidyl acrylate, y-(acryloyloxypropyl)trimethoxysilane, acrylic acid adduct with Ethylene Oxide, Trifluoromethylmethyl Acrylate, 2-Trifluoromethylethyl Acrylate, 2-Perfluoroethyl Acrylate, 2-Perfluoroethyl-2-Perfluorobutylethyl Acrylate, 2-Perfluoroethyl Acrylate, Perfluoromethyl Acrylate, Diperfluoroacrylate methylmethyl, 2-perfluoromethyl-2-perfluoroethyl acrylate, 2-perfluorohexylethyl acrylate, 2-perfluorodecylethyl acrylate, and 2-perfluorohexadecylethyl acrylate; α-alkoxyacrylate esters such as methyl α-methoxyacrylate and methyl α-ethoxyacrylate; crotonate esters such as methyl crotonate and ethyl crotonate; 3-alkoxyacrylate esters such as 3-methoxyacrylate esters; (meth)acrylamides such as N-isopropyl(meth)acrylamide, N-t-butyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-diethyl(meth)acrylamide; Methyl 2-phenyl acrylate, ethyl 2-phenyl acrylate, n-butyl 2-bromoacrylate, methyl 2-bromomethyl acrylate, ethyl 2-bromomethyl acrylate, methyl vinyl ketone, ethyl vinyl ketone, methyl isopropenyl ketone and ethyl isopropenyl ketone. The additional monomers may be used singly or two or more may be used in combination.

The content of the monomeric units obtained from the additional monomer is preferably not more than 10% by mass, and more preferably not more than 5% by mass with respect to all the monomeric units in the methacrylic polymeric block (A). When the (meth)acrylic block copolymer contains a plurality of methacrylic polymeric blocks (A), the content of the monomeric units obtained from the additional monomer is, in a desired embodiment, preferably not more than 10% by mass, and more preferably not more than 5% by mass in each of the polymeric blocks.

The number average molecular weight of the methacrylic polymeric block (A) is, although not particularly limited, preferably in the range of not less than 500 and not more than 100,000, and more preferably in the range of not less than 1,000 and not more than 50,000 from points of view such as handling, viscosity and the mechanical characteristics of the (meth)acrylic block copolymer that is obtained. When the (meth)acrylic block copolymer contains a plurality of methacrylic polymer blocks (A), the number average molecular weight of each of the polymer blocks is preferably in the above range.

In the present specification, the number average molecular weight and weight average molecular weight described below are values measured by gel permeation chromatography (GPC) (relative to standard polystyrenes).

The content of the methacrylic polymer block (A) in the (meth)acrylic block copolymer described herein is not particularly limited, but is preferably not less than 1% by mass and not more than 70% by mass, more preferably not less than 1% by mass and not more than 60% by mass, and even more preferably not less than 2% by mass and not more than 50% by mass. When the content is 70% by mass or less, the cured products obtained by curing the (meth)acrylic block copolymer described in this document tend to achieve excellent flexibility. When the content is 1% by mass or more, the (meth)acrylic block copolymer described herein tends to exhibit excellent curing speed when irradiated with active energy rays. In the case that the (meth)acrylic block copolymer includes a plurality of methacrylic polymer blocks (A), it is preferable that the total content of all methacrylic polymer blocks (A) satisfies the above value.

Acrylic polymer blocks (B)

The (meth)acrylic block copolymer includes an acrylic polymer block (B) having no active energy ray curable groups.

In the present specification, active energy ray-curable groups mean functional groups that exhibit polymerization capability when irradiated with the above-described active energy rays. Examples of active energy ray curable groups include, for example, functional groups having an ethylenic double bond (in particular, an ethylenic double bond represented by the general formula CH2=CR- (where R is an alkyl group or a carbon atom). hydrogen)) such as the partial structure (1) described above, methallyl group, allyl group, (meth)acryloyl group, vinyl group, vinyloxy group, 1,3-dienyl group and styryl group; and functional groups including epoxy group, oxetanyl group, thiol group, maleimide group, etc.

The acrylic polymer block (B) preferably includes monomeric units derived from an acrylate ester.

Examples of acrylate esters include, for example, monoacrylate esters such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, n- hexyl, n-heptyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, isooctyl acrylate, isobornyl acrylate, dodecyl acrylate, cyclohexyl acrylate, 2-methoxyethyl acrylate, 2-methoxypropyl acrylate, 3-methoxypropyl, 2-methoxybutyl acrylate, 4-methoxybutyl acrylate, 2-ethoxyethyl acrylate, 3-ethoxypropyl acrylate, 4-ethoxybutyl acrylate, methoxydiethylene glycol acrylate, ethoxydiethylene glycol acrylate, methoxytriethylene glycol acrylate, ethoxytriethylene glycol acrylate, Methoxydipropylene glycol acrylate, Ethoxydipropylene glycol acrylate, Methoxytripropylene glycol acrylate, Ethoxytripropylene glycol acrylate, Trimethoxysilylpropyl acrylate, N,N-dimethylaminoethyl acrylate, N,N-d acrylate ethylaminoethyl, phenyl acrylate, naphthyl acrylate, 2-(trimethylsilyloxy)ethyl acrylate and 3-(trimethylsilyloxy)propyl acrylate. Of these, alkyl acrylates having an alkyl group with 4 or more carbon atoms, such as n-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate and n-butyl acrylate, are preferable. octyl, and 2-methoxyethyl acrylate. More preferable are 2-ethylhexyl acrylate, n-butyl acrylate and 2-methoxyethyl acrylate. The acrylate esters may be used singly or two or more may be used in combination.

The content of the monomeric units obtained from the acrylate ester is preferably not less than 90% by mass with respect to all the monomeric units in the acrylic polymer block (B), and more preferably not less than 95% by mass, and can be 100% by mass. The acrylic polymer block (B) may include monomeric units derived from an additional monomer other than the acrylate esters described above. Examples of such additional monomers include alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, cyclohexyl methacrylate, 2- ethylhexyl, isobornyl methacrylate, and dodecyl methacrylate; Methacrylate esters such as 2-methoxyethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxybutyl methacrylate, trimethoxysilylpropyl methacrylate, 2-aminoethyl methacrylate, N,N-dimethylaminoethyl methacrylate, N,N-diethylaminoethyl methacrylate, methacrylate Phenyl Methacrylate, Naphthyl Methacrylate, 2-(Trimethylsilyloxy)ethyl Methacrylate, 3-(Trimethylsilyloxy)propyl Methacrylate, Glycidyl Methacrylate, Y -(Methacryloyloxypropyl)Trimethoxysilane, Ethylene Oxide Adduct of Methacrylic Acid, Trifluoromethylmethyl Methacrylate, Methacrylate 2-trifluoromethylethyl, 2-perfluoroethylmethyl methacrylate, 2-perfluoroethyl-2-perfluorobutylethyl methacrylate, 2-perfluoroethyl methacrylate, perfluoromethyl methacrylate, diperfluoromethylmethyl methacrylate, 2-perfluoromethyl-2-perfluoroethylmethyl methacrylate, 2-perfluorohexylethyl methacrylate , 2-perfluorodecylethyl methacrylate and 2-perfluorohexadecylethyl methacrylate; α - alkoxyacrylate esters such as methyl α - methoxyacrylate and methyl α - ethoxyacrylate; crotonate esters such as methyl crotonate and ethyl crotonate; 3-alkoxyacrylate esters such as 3-methoxyacrylate esters; (meth)acrylamides such as N-isopropyl(meth)acrylamide, N-t-butyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-diethyl(meth)acrylamide; methyl vinyl ketone, ethyl vinyl ketone, methyl isopropenyl ketone and ethyl isopropenyl ketone. The additional monomers may be used singly or two or more may be used in combination. The content of the monomeric units obtained from the additional monomer is preferably not more than 10% by mass, and more preferably not more than 5% by mass with respect to all the monomeric units in the acrylic polymer block (B).

The number average molecular weight of the acrylic polymer block (B) is, though not particularly limited, preferably in the range of 3,000 to 300,000, and more preferably in the range of 5,000 to 200,000 from the viewpoints such as workability, viscosity and the mechanical characteristics of the (meth)acrylic block copolymer that is obtained. When the (meth)acrylic block copolymer contains a plurality of acrylic polymer blocks (B), the number average molecular weight of each of the polymer blocks is preferably in the above range.

The content of the acrylic polymer block (B) in the (meth)acrylic block copolymer described herein is not particularly limited, but is preferably not less than 30% by mass and not more than 99% by mass, more preferably not less than 40% by mass and not more than 99% by mass, and even more preferably not less than 50% by mass and not more than 98% by mass. When the content is 30% by mass or more, the cured products obtained by curing the (meth)acrylic block copolymer described in this document tend to achieve excellent flexibility. When the content is 99% by mass or less, the (meth)acrylic block copolymer described herein tends to exhibit excellent curing speed when radiates with rays of active energy. In the case that the (meth)acrylic block copolymer includes a plurality of acrylic polymer blocks (B), it is preferable that the total content of all acrylic polymer blocks (B) satisfies the above value.

(Meth)acrylic block copolymers

The number average molecular weight (Mn) of the (meth)acrylic block copolymer described herein is not particularly limited, but from the viewpoints such as workability, viscosity and mechanical properties, it is preferably not less than 4,000 and no more than 400,000, more preferably no less than 7,000 and no more than 200,000, and even more preferably no less than 10,000 and no more than 100,000. The molecular weight distribution (Mw/Mn), that is, the weight average molecular weight (Mw)/number average molecular weight (Mn) ratio of the (meth)acrylic block copolymer described herein is preferably not more than 2 .00, more preferably in the range of not less than 1.01 and not more than 2.00, still more preferably in the range of not less than 1.01 and not more than 1.80, and most preferably in the range of not less than 1.01 and not more than 1.50.

The (meth)acrylic block copolymer described herein is a block copolymer that includes at least one methacrylic polymer block (A) and at least one acrylic polymer block (B). The (meth)acrylic block copolymer may have an additional polymer block in addition to the methacrylic polymer block (A) and the acrylic polymer block (B). The number of the respective polymer blocks and the order in which they are joined are not particularly limited. From the viewpoint of active energy ray curability, it is preferable that the methacrylic polymer block (A) defines at least one end of the (meth)acrylic block copolymer. From the standpoint of ease of production of the (meth)acrylic block copolymer, the polymer is more preferably linear. In particular, the copolymer is more preferably a diblock copolymer composed of a methacrylic polymer block (A) and an acrylic polymer block (B) coupled together, or a triblock copolymer in which a methacrylic polymer block (A) is attached to both ends of an acrylic polymer block (B).

The (meth)acrylic block copolymer described herein can be produced by any method without limitation, but is preferably produced by anionic polymerization or radical polymerization. From the point of view of polymerization control, the copolymer is more preferably produced by living anionic polymerization or radical living polymerization, and even more preferably it is produced by living anionic polymerization.

Examples of living radical polymerization processes include polymerization with a chain transfer agent such as polysulfide, polymerization with a cobalt porphyrin complex, polymerization with a nitroxide (see WO 2004/014926), polymerization using a heteroelement compound of a higher period, such as an organotellurium compound (see Japanese Patent No. 3839829), reversible addition-fragmentation chain transfer polymerization (RAFT) (see Japanese Patent No. 3639859), and atom transfer radical polymerization (ATRP) (see Japanese Patent No. 3040172 and WO 2004/013192). Of these living radical polymerization processes, atom transfer radical polymerization is preferable. A more preferred process is atom transfer radical polymerization which uses an organic halide or halogenated sulfonyl compound as initiator and is catalyzed by a metal complex having at least one central metal selected from Fe, Ru, Ni and Cu.

Examples of the living anionic polymerization processes include living polymerization using an organic rare earth metal complex as a polymerization initiator (see JP-A-H06-93060), living anionic polymerization performed with an organic alkali metal compound as a polymerization initiator polymerization in the presence of a mineral acid salt such as an alkali or alkaline earth metal salt (see JP-A-H05-507737), and living anionic polymerization carried out with an organic alkali metal compound as a polymerization initiator in the presence of a compound organoaluminum (see JP-A-H11-335432 and WO 2013/141105). Of these living anionic polymerization processes, living anionic polymerization performed with an organic alkali metal compound as a polymerization initiator in the presence of an organoaluminum compound is advantageous because the (meth)acrylic block copolymer described here can be produced directly and efficiently. For the same reason, a more preferred process is living anionic polymerization performed with an organolithium compound as the polymerization initiator in the presence of an organoaluminum compound and a Lewis base.

Examples of the organolithium compounds include, for example, t-butyllithium, 1,1-dimethylpropyllithium, 1,1-diphenylhexyllithium, 1,1-diphenyl-3-methylpentyllithium, ethyl a-lithioisobutyrate, Butyl a-Lithioisobutyrate, Methyl a-Lithioisobutyrate, Isopropyl Lithium, sec-Butyl Lithium, 1-Methylbutyl Lithium, 2-Ethylpropyl Lithium, 1-Methylpentyl Lithium, Cyclohexyl Lithium, Diphenylmethyl Lithium, amethylbenzyl- lithium, methyl lithium, n-propyl lithium, n-butyl lithium and n-pentyl lithium. From the standpoint of availability and ability to initiate anionic polymerization, the preferred organolithium compounds are those compounds with 3 to 40 carbon atoms having a chemical structure having a secondary carbon atom as the anion center, such as isopropyllithium, sec-butyllithium, 1-methylbutyllithium, 1-methylpentyllithium, cyclohexyllithium, diphenylmethyllithium and amethylbenzyllithium, with sec-butyllithium being particularly preferred. The organolithium compounds may be used singly or two or more may be used in combination.

The amount in which the organolithium compound is used can be determined in relation to the amount of the monomers used, according to the target number average molecular weight of the (meth)acrylic block copolymer.

Examples of the organoaluminum compounds include the organoaluminum compounds represented by the following general formula (A-1) or (A-2).

AlR2(R3)(R4) (A-1)

In the general formula (A-1), R2 indicates a monovalent saturated hydrocarbon group, a monovalent aromatic hydrocarbon group, an alkoxy group, an aryloxy group or an N,N-disubstituted amino group, and R3 and R4 each independently indicate a aryloxy group or R3 and R4 are bonded together to form an arylenedioxy group.

AlR5(R6)(R7) (A-2)

In the general formula (A-2), R5 indicates an aryloxy group, and each of R6 and R7 independently indicates a monovalent saturated hydrocarbon group, monovalent aromatic hydrocarbon group, alkoxy group or N,N-disubstituted amino group.

Examples of the aryloxy groups indicated by R2, R3, R4 and R5 independently in the general formulas (A-1) and (A-2) include, for example, phenoxy group, 2-methylphenoxy group, 4-methylphenoxy group, 2,6-dimethylphenoxy, 2,4-di-t-butylphenoxy group, 2,6-di-t-butylphenoxy group, 2,6-di-t-butyl-4-methylphenoxy group, 2,6-di- t-butyl-4-ethylphenoxy, 2,6-diphenylphenoxy group, 1-naphthoxy group, 2-naphthoxy group, 9-phenanthryloxy group, 1-pyrenyloxy group, and 7-methoxy-2-naphthoxy group.

Examples of the arylenedioxy groups formed by R3 and R4 linked together in the general formula (A-1) include, for example, functional groups obtained from compounds having two phenolic hydroxyl groups by removing hydrogen atoms from the two phenolic hydroxyl groups, such as 2,2'-biphenol, 2,2'-methylenebisphenol, 2,2'-methylenebis(4-methyl-6-t-butylphenol), (R)-(+)-1,1 '-bi-2-naphthol and (S)-(-)-1,1 '-bi-2-naphthol.

The aryloxy and arylenedioxy groups described above may be substituted with a substituent in place of one or more hydrogen atoms. Examples of the substituents include, for example, alkoxy groups such as methoxy group, ethoxy group, isopropoxy group and t-butoxy group; and halogen atoms such as chlorine atom and bromine atom.

Referring to R2, R6 and R7 in the general formulas (A-1) and (A-2), examples of monovalent saturated hydrocarbon groups include, for example, alkyl groups such as methyl group, ethyl group, n-propyl group , isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, 2-methylbutyl group, 3-methylbutyl group, n-octyl group and 2-ethylhexyl group, and cycloalkyl groups such as cyclohexyl group ; examples of monovalent aromatic hydrocarbon groups include, for example, aryl groups such as phenyl group, and aralkyl groups such as benzyl group; examples of alkoxy groups include, for example, methoxy group, ethoxy group, isopropoxy group, and t-butoxy group; and examples of N,N-disubstituted amino groups include, for example, dialkylamino groups such as dimethylamino group, diethylamino group and diisopropylamino group, and bis(trimethylsilyl)amino group. The monovalent saturated hydrocarbon groups, monovalent aromatic hydrocarbon groups, alkoxy groups and N,N-disubstituted amino groups described above may be substituted with a substituent in place of one or more hydrogen atoms. Examples of the substituents include, for example, alkoxy groups such as methoxy group, ethoxy group, isopropoxy group and t-butoxy group; and halogen atoms such as chlorine atom and bromine atom.

Examples of the organoaluminum compounds represented by the general formula (A-1) include, for example, ethylbis(2,6-di-t-butyl-4-methylphenoxy)aluminum, ethylbis(2,6-di-t- butylphenoxy)aluminum, ethyl[2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, isobutylbis(2,6-di-t-butyl-4-methylphenoxy)aluminum, isobutylbis(2,6- di-t-butylphenoxy)aluminum, isobutyl[2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, n-octylbis(2,6-di-t-butyl-4-methylphenoxy)aluminum, n-octylbis(2,6-di-t-butylphenoxy)aluminum, n-octyl[2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, methoxybis(2,6-di-t- butyl-4-methylphenoxy)aluminum, methoxybis(2,6-di-t-butylphenoxy)aluminum, methoxy[2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, ethoxybis(2, 6- di-t-butyl-4-methylphenoxy)aluminum, ethoxybis(2,6-di-t-butylphenoxy)aluminum, ethoxy[2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, isopropoxybis( 2,6-di-t-butyl-4-methylphenoxy)aluminum, isopropoxybis(2,6-di-t-butylphenoxy)aluminum, isopropoxy[2,2'-methylenebis(4-methyl-6-t-butylphe noxy)]aluminum, t-butoxybis(2,6-di-t-butyl-4-methylphenoxy)aluminum, t-butoxybis(2,6-di-t-butylphenoxy)-aluminum, t-butoxy[2,2' -methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, tris(2,6-di-t-butyl-4-methylphenoxy) aluminum and tris(2,6-diphenylphenoxy)aluminum. From the points of view such as polymerization initiation efficiency, living properties of polymer terminal anions, availability and easy handling, preferred compounds are, among others, isobutylbis(2,6-di-t-butyl -4-methylphenoxy)aluminum, isobutylbis(2,6-di-t-butylphenoxy)aluminum and isobutyl[2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum.

Examples of the organoaluminum compounds represented by the general formula (A-2) include, for example, diethyl(2,6-di-t-butyl-4-methylphenoxy)aluminum, diethyl(2,6-di-t- butylphenoxy)aluminum, diisobutyl(2,6-di-t-butyl-4-methylphenoxy)-aluminum, diisobutyl(2,6-di-t-butylphenoxy)aluminum, di-n-octyl(2,6-di-t -butyl-4-methylphenoxy)aluminum and di-n-octyl(2,6-di-tbutylphenoxy)aluminum. The organoaluminum compounds may be used singly or two or more may be used in combination.

The organoaluminum compound can be used in a suitable amount which is appropriately selected in accordance with factors such as the type of solvent and various other polymerization conditions. From the point In view of the polymerization rate, it is usually preferable that the amount is in the range of 1.0 to 10.0 mol per 1 mol of the organolithium compound, and more preferably in the range of 1.1 to 5.0 mol. , and even more preferably in the range of 1.2 to 4.0 mol. The use of more than 10.0 mol of the organoaluminum compound per 1 mol of the organolithium compound tends to give rise to economic disadvantages. If the amount is less than 1.0 mol per 1 mol of the organolithium compound, the polymerization initiation efficiency tends to lower.

Examples of Lewis bases include, for example, compounds having an ether bond and/or a tertiary amine structure in the molecule.

Examples of compounds having an ether bond in the molecule that are used as Lewis bases include ethers. From the viewpoint of high polymerization initiation efficiency and living properties of terminal anions of the polymer, preferred ethers are cyclic ethers having two or more ether linkages in the molecule or acyclic ethers having one or more ether bonds. more ether bonds in the molecule. Examples of cyclic ethers having two or more ether linkages in the molecule include, for example, crown ethers such as 12-crown-4, 15-crown-5, and 18-crown-6. Examples of acyclic ethers having one or more ether linkages in the molecule include, for example, acyclic monoethers such as dimethyl ether, diethyl ether, diisopropyl ether, dibutyl ether, and anisole; acyclic diethers such as 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-diisopropoxyethane, 1,2-dibutoxyethane, 1,2-diphenoxyethane, 1,2-dimethoxypropane, 1,2-diethoxypropane, 1,2- diisopropoxypropane, 1,2-dibutoxypropane, 1,2-diphenoxypropane, 1,3-dimethoxypropane, 1,3-diethoxypropane, 1,3-diisopropoxypropane, 1,3-dibutoxypropane, 1,3-diphenoxypropane, 1,4-dimethoxybutane, 1,4-diethoxybutane, 1,4-diisopropoxybutane, 1,4-dibutoxybutane, and 1,4-diphenoxybutane; and acyclic polyethers such as diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dibutylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol diethyl ether, dibutylene glycol diethyl ether, triethylene glycol dimethyl ether, tripropylene glycol dimethyl ether, tributylene glycol dimethyl ether, triethylene glycol diethyl ether, tripropylene glycol diethyl ether, diethyl ether of tributylene glycol, tetraethylene glycol dimethyl ether, tetrapropylene glycol dimethyl ether, tetrabutylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetrapropylene glycol diethyl ether and tetrabutylene glycol diethyl ether. From the viewpoints such as side reaction control and availability, acyclic ethers having one or two ether linkages in the molecule are preferable, and diethyl ether or 1,2-dimethoxyethane is more preferable.

Examples of compounds having a tertiary amine structure in the molecule that are used as Lewis bases include tertiary polyamines. Tertiary polyamines are compounds that have two or more tertiary amine structures in the molecule. Examples of tertiary polyamines include, for example, chain polyamines such as N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetraethylethylenediamine, N,N,N',N",N" -pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine and tris[2-(dimethylamino)ethyl]amine; non-aromatic heterocyclic compounds such as 1,3,5-trimethylhexahydro-1,3,5-triazine, 1,4,7-trimethyl-1,4,7-triazacyclononane and 1,4,7,10,13,16- hexamethyl-1,4,7,10,13,16-hexaazacyclooctadecane; and aromatic heterocyclic compounds such as 2,2'-bipyridyl and 2,2',6',2"-terpyridine.

Furthermore, the Lewis base may be a compound having one or more ether linkages and one or more tertiary amine structures in the molecule. Examples of such compounds include, for example, tris[2-(2-methoxyethoxy)ethyl]amine.

The Lewis bases can be used alone or two or more can be used in combination.

From the viewpoints such as the polymerization initiation efficiency and the living properties of the terminal anions of the polymer, the amount in which the Lewis base is used is preferably in the range of 0.3 to 5.0 mol per 1 mol of the organolithium compound, and is more preferably in the range of 0.5 to 3.0 mol, and even more preferably in the range of 1.0 to 2.0 mol. The use of more than 5.0 mol of the Lewis base per 1 mol of the organolithium compound tends to give rise to economic disadvantages. If the amount is less than 0.3 mol per 1 mol of the organolithium compound, the polymerization initiation efficiency tends to lower.

The amount of Lewis base is preferably in the range of 0.2 to 1.2 mol, and more preferably in the range of 0.3 to 1.0 mol per 1 mol of the organoaluminum compound.

The living anionic polymerization is preferably carried out in the presence of an organic solvent in order to carry out the polymerization at a controlled temperature and to make the system uniform so that the polymerization proceeds smoothly. From the viewpoints such as safety, immiscibility with the water used for washing the reaction liquid after polymerization, and ease of recovery and reuse, preferred organic solvents are, among others, hydrocarbons such as toluene, xylene, cyclohexane and methylcyclohexane; halogenated hydrocarbons such as chloroform, methylene chloride, and carbon tetrachloride; and esters such as dimethyl phthalate. The organic solvents may be used singly or two or more may be used in combination. To ensure that the polymerization will proceed smoothly, it is preferable that the organic solvent is previously dried and deaerated in the presence of an inert gas.

In living anionic polymerization, additives can be added to the reaction system as required. Examples of such additives include, for example, inorganic salts such as lithium chloride; metal alkoxides such as lithium methoxyethoxyethoxide and potassium t-butoxide; tetraethylammonium chloride and tetraethylphosphonium bromide.

The living anionic polymerization is preferably carried out at -30 to 25°C. Below -30°C, the polymerization rate decreases and the productivity tends to deteriorate. If, on the other hand, the temperature is higher than 25°C, it tends to be difficult to polymerize monomers including a methacrylate ester of the general formula (2) with good living properties.

The living anionic polymerization is preferably carried out in an atmosphere of an inert gas such as nitrogen, argon or helium. Furthermore, it is preferable that the polymerization is carried out while stirring enough for the reaction system to become uniform.

In the living anionic polymerization, the organolithium compound, the organoaluminum compound, the Lewis base and the monomers are preferably added to the reaction system in such a way that the Lewis base is contacted with the organoaluminum compound prior to contact. with the organolithium compound. The organoaluminum compound can be added to the reaction system before or at the same time as the monomers. When the organoaluminum compound and the monomers are added to the reaction system at the same time, the organoaluminum compound can be mixed with the monomers beforehand, and the resulting mixture can be added.

The living anionic polymerization can be terminated by adding a polymerization terminator such as a protic compound, eg, methanol, to the reaction liquid; a methanolic solution of acetic acid or hydrochloric acid; or an aqueous solution of acetic acid or hydrochloric acid. It is usually preferable that the amount of the polymerization terminator is in the range of 1 to 1,000 mol per 1 mol of the organolithium compound used.

After the completion of the living anionic polymerization, the (meth)acrylic block copolymer can be separated and collected from the reaction liquid by a known method, for example, by a method in which the reaction liquid is poured into an inefficient solvent. for the (meth)acrylic block copolymer to cause precipitation, or a method in which the (meth)acrylic block copolymer is collected by distilling off the organic solvent from the reaction liquid.

If the (meth)acrylic block copolymer that has been separated and collected contains residual metal components derived from the organolithium compound and the organoaluminum compound, such residual metals may cause problems such as a decrease in the properties of the (meth)block copolymer. acrylics, and little transparency. Therefore, it is preferable to remove the metal components derived from the organolithium compound and the organoaluminum compound after the completion of the living anionic polymerization. Some effective methods to remove such metal components are washing treatment with an acidic aqueous solution and adsorption treatment with an adsorbent such as ion exchange resin, Celite or activated carbon. Examples of the acidic aqueous solutions that can be used herein include, for example, hydrochloric acid, sulfuric acid aqueous solution, nitric acid aqueous solution, acetic acid aqueous solution, propionic acid aqueous solution and citric acid aqueous solution.

In the production of the (meth)acrylic block copolymer described herein, the partial structure (1) can be introduced by the method in which monomers including a methacrylate ester of the general formula (2) are polymerized to form a methacrylic polymer block (A). An alternative method is such that a polymer block containing a partial structure that is a precursor to partial structure (1) (henceforth, the structure will be written as "precursor structure") is first formed and then the precursor structure is converted in the partial structure (1). Such a polymer block containing a precursor structure can be obtained by polymerizing monomers including a compound having a polymerizable functional group and a precursor structure (hereinafter, the compound will be referred to as "polymerizable precursor"). Examples of the polymerizable functional groups include, for example, styryl group, 1,3-dienyl group, vinyloxy group and (meth)acryloyl group, with (meth)acryloyl group being preferable. Examples of precursor structures include hydroxyl groups, hydroxyl groups protected with a protecting group (such as a silyloxy group, an acyloxy group, or an alkoxy group), amino groups, amino groups protected with a protecting group, thiol groups, thiol groups protected with a protecting group. protecting and isocyanate groups.

A polymer block containing a hydroxyl group as a precursor structure can be reacted with a compound having a partial structure (1) and a partial structure reactive with the hydroxyl group (such as a carboxylic acid, an ester or a carbonyl halide) to form a block of methacrylic polymer (A). In addition, a polymer block containing, as a precursor structure, a hydroxyl group protected with a protecting group may be deprotected and the resulting hydroxyl group may be reacted in a manner similar to that described above to form a methacrylic polymer block (A).

A polymer block containing an amino group as a precursor structure can react with a compound having a partial structure (1) and a partial structure reactive with the amino group (such as a carboxylic acid, a carboxylic anhydride, an ester, a halide of carbonyl, an aldehyde group or an isocyanate group) to form a methacrylic polymeric block (A). In addition, a polymer block containing, as a precursor structure, an amino group protected with a protecting group can be deprotected and the resulting amino group can be reacted in a similar manner as described above to form a methacrylic polymer block (A).

A polymer block containing a thiol group as a precursor structure can react with a compound having a partial structure (1) and a partial structure reactive with the thiol group (such as a carboxylic acid, a carboxylic anhydride, an ester, a halide of carbonyl, an isocyanate group or a carbon-carbon double bond) to form a methacrylic polymeric block (A). In addition, a polymer block containing, as a structure As a precursor, a thiol group protected with a protecting group may be deprotected and the resulting thiol group may be reacted in a similar manner as described above to form a methacrylic polymer block (A).

A polymer block containing an isocyanate group as a precursor structure can react with a compound having a partial structure (1) and a partial structure reactive with the isocyanate group (such as a hydroxyl group) to form a methacrylic polymer block (A) .

In the production of the (meth)acrylic block copolymer described herein, the methacrylic polymer block (A) is preferably formed by polymerization, typically living anionic polymerization, of monomers including a methacrylate ester of general formula (2). Such a method is advantageous in that the partial structure (1) can be inserted easily and directly.

Active energy beam curable compositions

The (meth)acrylic block copolymer described herein is used as a material for an active energy ray curable composition.

The active energy ray curable composition may contain a photopolymerization initiator. Examples of photopolymerization initiators include, for example, carbonyl compounds such as acetophenones (eg, 1-hydroxycyclohexylphenylketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-2-methyl-1-phenylpropane -1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone), benzophenones (for example, benzophenone, benzoylbenzoic acid, hydroxybenzophenone, 3,3'-dimethyl-4-methoxybenzophenone and benzophenone acrylated), Michler's ketones (eg Michler's ketone) and benzoins (eg benzoin, benzoin methyl ether and benzoin isopropyl ether); sulfur compounds such as tetramethylthiuram monosulfide and thioxanthones (eg, thioxanthone and 2-chlorothioxanthone); phosphorous compounds such as acylphosphine oxides (eg, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide); titanium compounds such as titanocenes (eg bis(q5-2,4-cyclopentadien-1-yl)-bis(2,5-difluoro-3-(1 H-pyrrol-1-yl)-phenyl)titanium) ; and azo compounds (eg, azobisisobutyronitrile). The photopolymerization initiators may be used singly or two or more may be used in combination. Of these, acetophenones and benzophenones are preferable.

When the photopolymerization initiator is used, the content thereof is preferably not less than 0.01 part by mass and not more than 10 parts by mass, and more preferably not less than 0.05 part by mass and not more than 8 parts by mass. by mass relative to 100 parts by mass of the (meth)acrylic block copolymer described herein. When the content is 0.01 part by mass or more, the active energy ray curable composition tends to achieve good curability. When the content is 10 parts by mass or less, the resulting cured products tend to exhibit good heat resistance.

In addition, the active energy ray curable composition may contain a sensitizer as required. Examples of sensitizers include, for example, n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthiourea, triethylamine, and diethylaminoethyl methacrylate. Of these, diethylaminoethyl methacrylate and triethylamine are preferable.

When the photopolymerization initiator and the sensitizer are used simultaneously, the mass ratio of the photopolymerization initiator to the sensitizer is preferably in the range of 10:90 to 90:10, and more preferably in the range of 20:80 to 80:20. .

In the active energy ray curable composition of the invention, the content of the (meth)acrylic block copolymer can be appropriately controlled in accordance with factors such as the intended use application. From the viewpoint of mechanical characteristics, the content is preferably not less than 1% by mass, more preferably not less than 10% by mass, and even more preferably not less than 30% by mass, and preferably not more than 99%. mass. more preferably not more than 80% by mass, and even more preferably not more than 70% by mass. The content can be 100% by mass.

The active energy ray curable composition of the invention may further include a solvent. The addition of a solvent can control viscosity and improve application properties. Furthermore, the addition of a solvent facilitates the dissolution or dispersion of the components in the active energy ray curable composition.

Examples of solvents include, for example, aromatic hydrocarbons such as benzene, toluene, and chlorobenzene; aliphatic or alicyclic hydrocarbons such as pentane, hexane, cyclohexane, and heptane; halogenated hydrocarbons such as carbon tetrachloride, chloroform, and ethylene dichloride; nitro compounds such as nitromethane and nitrobenzene; ethers such as diethyl ether, methyl t-butyl ether, tetrahydrofuran, and 1,4-dioxane; esters such as methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, and amyl acetate; amides such as dimethylformamide; alcohols such as methanol, ethanol, and propanol; and ketones such as acetone, methyl ethyl ketone, and cyclohexanone.

When the solvent is added, the content thereof with respect to 100 parts by mass of the (meth)acrylic block copolymer used in the present invention is preferably not less than 1 part by mass, more preferably not less than 10 parts by mass, and even more preferably not less than 30 parts by mass, and preferably not more than 500 parts by mass, more preferably not more than 300 parts by mass, and still more preferably not more than 200 parts by mass.

As long as the advantageous effects of the invention are still achieved, the active energy ray curable composition may contain a reactive diluent which is other than the (meth)acrylic block copolymers described herein and exhibits polymerization ability when irradiated with energy rays. active energy. Said reactive diluents are not particularly limited and may be any kind of compound which shows polymerization ability when irradiated with active energy rays. Examples include, for example, styrene derivatives such as styrene, indene, p-methylstyrene, a-methylstyrene, p-methoxystyrene, p-t-butoxystyrene, p-chloromethylstyrene, p-acetoxystyrene, and divinylbenzene; vinyl esters of fatty acids such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl benzoate, and vinyl cinnamate; (meth)acrylic acid derivatives such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, (meth)acrylate )amyl acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, ( noctyl meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, Dodecyl (meth)acrylate, Stearyl (meth)acrylate, Isostearyl (meth)acrylate, Benzyl (meth)acrylate, Isobornyl (meth)acrylate, Bornyl (meth)acrylate, Tricyclodecanyl (meth)acrylate, ( Dicyclopentanyl meth)acrylate, Dicyclopentenyloxyethyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, ( 4-hydroxybutyl meth)acrylate or, tetrahydrofurfuryl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, phenoxyethyl (meth)acrylate, polyethylene glycol mono(meth)acrylate ester, polypropylene glycol mono(meth)acrylate ester, Methoxyethylene glycol (meth)acrylate, Ethoxyethyl (meth)acrylate, Methoxypolyethylene glycol (meth)acrylate, Methoxypolypropylene glycol (meth)acrylate, Dimethylaminoethyl (meth)acrylate, Diethylaminoethyl (meth)acrylate, 7-amino (meth)acrylate -3,7-dimethyloctyl, 4-(meth)acryloylmorpholine, trimethylolpropane tri(meth)acrylate, trimethylolpropane ethoxytri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethylene glycol di(meth)acrylate, di(meth) Triethylene Glycol Acrylate, Tetraethylene Glycol Di(Meth)acrylate, Tricyclodecanediyldimethanol Di(Meth)acrylate, Polyethylene Glycol Di(Meth)acrylate, Butanediol 1,4-Di(Meth)acrylate, 1,6-Di(Meth)acrylate hexanediol, neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, diglyci adduct Bisphenol A diethyl ether with (meth)acrylic acid at both ends, pentaerythritol tetra(meth)acrylate, 2,4,6-trioxohexahydro-1,3,5-triazine-1,3,5-tri(meth)acrylate trisethanol, N,N'-bis[2-((meth)acryloyloxy)ethyl]-N"-(2-hydroxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H) -trione, tricyclodecane dimethanol di(meth)acrylate, di(meth)acrylate of a diol which is an adduct of bisphenol A with ethylene oxide or propylene oxide, di(meth)acrylate of a diol which is an adduct of bisphenol A hydrogenated with ethylene oxide or propylene oxide, epoxy (meth)acrylate which is an adduct of diglycidyl ether with (meth)acrylate and cyclohexanedimethanol di(meth)acrylate; epoxy acrylate resins such as bisphenol A epoxy acrylate resin, phenol novolac epoxy acrylate resin and cresol novolac epoxy acrylate resin; carboxyl group modified epoxy acrylate resins; urethane acrylate resins obtained by reacting a urethane resin formed between a polyol (such as polytetramethylene glycol, ethylene glycol polyester diol and adipic acid, β-caprolactone modified polyester diol, polypropylene glycol, polyethylene glycol, polycarbonate diol, hydroxyl-terminated hydrogenated polyisoprene , hydroxyl-terminated polybutadiene or hydroxyl-terminated polyisobutylene) and an organic isocyanate (such as toluylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate or xylylene diisocyanate), with a hydroxyl-containing (meth)acrylate (such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate or pentaerythritol triacrylate); resins obtained by introducing a (meth)acryloyl group into the above polyols through an ester bond; polyester acrylate resins; and epoxy compounds such as epoxidized soybean oil and benzyl epoxystearate. From the viewpoint of curability, acrylate monomers such as n-octyl acrylate, isooctyl acrylate and 2-ethylhexyl acrylate are preferably used. The reactive diluents may be used singly or two or more may be used in combination.

When the active energy ray curable composition contains the reactive diluent, the content thereof with respect to 100 parts by mass of the (meth)acrylic block copolymer described herein is preferably not less than 5 parts by mass, and more. preferably not less than 20 parts by mass, and preferably not more than 900 parts by mass, more preferably not more than 400 parts by mass, and even more preferably not more than 150 parts by mass. When the content is 5 parts by mass or more, the active energy ray curable composition attains a lower viscosity. When the content is 900 parts by mass or less, the active energy ray curable composition tends to exhibit higher curing speed and achieve more excellent flexibility of cured products.

The active energy ray curable composition may contain various additives free of active energy ray curable groups, such as plasticizers, tackifiers, softeners, fillers, stabilizers, pigments and colorants, as long as the curability of the composition is ensured. composition will not be significantly affected.

Plasticizers may be added to the active energy beam curable composition for such purposes as, for example, controlling the viscosity of the active energy beam curable composition and controlling the mechanical strength of cured products obtained by curing the curable composition. by rays of active energy. Examples of plasticizers include, for example, phthalate esters such as dibutyl phthalate, diheptyl phthalate, di(2-ethylhexyl) phthalate, and butylbenzyl phthalate; non-aromatic dibasic acid esters such as dioctyl adipate, dioctyl sebacate, dibutyl sebacate and isodecyl succinate; aliphatic esters such as butyl oleate and methyl acetylricinoleate; polyalkylene glycol esters such as diethylene glycol dibenzoate, triethylene glycol dibenzoate, and pentaerythritol ester; phosphate esters such as tricresyl phosphate and tributyl phosphate; esters trimellitates; diene (co)polymers such as polybutadiene, butadiene-acrylonitrile copolymer and polychloroprene; polybutene; polyisobutylene; chlorinated paraffins; hydrocarbon oils such as partially hydrogenated alkyldiphenyls and terphenyls; process oils; polyethers such as polyether polyols, eg, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol, and derivatives obtained by converting hydroxyl groups of polyether polyols to ester groups, ether groups, or the like; and polyesters obtained from a dibasic acid such as sebacic acid, adipic acid, azelaic acid or phthalic acid, and a dihydric alcohol such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol or dipropylene glycol. The term "(co)polymers" denotes both homopolymers and copolymers. The plasticizers may be used singly or two or more may be used in combination.

The molecular weight or number average molecular weight of the plasticizers is preferably from 400 to 15,000, more preferably from 800 to 10,000, and even more preferably from 1,000 to 8,000. The plasticizers may contain functional groups other than active energy ray curable groups (such as, for example, hydroxyl groups, carboxyl groups, and halogen groups) or may be free of such functional groups. Since the molecular weight or number average molecular weight of the plasticizer is 400 or more, the plasticizer does not bleed with time from a cured product of the active energy ray curable composition, and therefore it is possible to maintain the properties. starters for a long time. Since the molecular weight or number average molecular weight of the plasticizer is 15,000 or less, the active energy ray curable composition tends to exhibit good workability.

When the plasticizer is added to the active energy ray curable composition, the content thereof is preferably 5 to 150 parts by mass, more preferably 10 to 120 parts by mass, and still more preferably 20 to 100 parts by mass. relative to 100 parts by mass of the (meth)acrylic block copolymer described herein. When added in an amount of 5 parts by mass or more, the plasticizer tends to have marked effects, for example, in controlling properties and characteristics. When the content is 150 parts by mass or less, the cured products obtained by curing the active energy ray curable composition tend to achieve excellent mechanical strength.

Tackifiers may be added to the active energy ray curable composition for such purposes as, for example, imparting tack to cured products obtained from the active energy ray curable composition. Examples of tackifiers include, for example, tackifier resins such as coumarone-indene resins, phenolic resins, p-t-butylphenol-acetylene resins, phenol-formaldehyde resins, xylene-formaldehyde resins, aromatic hydrocarbon resins, hydrocarbon resins. aliphatics (for example, terpene resins), styrene resins (for example, polystyrene and poly-α-methylstyrene), polyhydric alcohol rosin esters, hydrogenated rosins, hydrogenated wood rosins, hydrogenated rosin esters with monoalcohols or polyhydric alcohols , and turpentine sticky resins. In particular, preferred tackifiers are aliphatic hydrocarbon resins, polyhydric alcohol rosin esters, hydrogenated rosins, hydrogenated wood rosins, and hydrogenated rosin esters with monoalcohols or polyhydric alcohols.

When the tackifier is added to the active energy ray curable composition, the content thereof is preferably 5 to 150 parts by mass, more preferably 10 to 120 parts by mass, and still more preferably 20 to 100 parts by mass. by mass relative to 100 parts by mass of the (meth)acrylic block copolymer described herein. When added in 5 mass parts or more, the tackifier tends to give cured products significant tack. When the content is 150 parts by mass or less, the cured products tend to achieve more excellent flexibility.

The active energy ray curable group-free additives may be organic compounds or inorganic compounds.

To cure the (meth)acrylic block copolymer described herein, or the active energy beam curable composition including the (meth)acrylic block copolymer, active energy beams can be applied with known devices. In the case of electron beams (EB), the acceleration voltage and dosage are appropriately in the range of 0.1 to 10 MeV and in the range of 1 to 500 kGy, respectively.

Ultraviolet lights can be applied using devices such as high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, metal halide lamps, xenon lamps, chemical lamps, and LEDs, each of which emits wavelength lights of 150-450 nm. The cumulative dose of the active energy rays is usually in the range of 10 to 20,000 mJ/cm2, and preferably in the range of 30 to 10,000 mJ/cm2. Irradiation with less than 10 mJ/cm2 tends to result in insufficient curing of the (meth)acrylic block copolymer. The (meth)acrylic block copolymer may degrade if the cumulative dose is greater than 20,000 mJ/cm2.

When the (meth)acrylic block copolymer described herein, or the active energy ray curable composition including the (meth)acrylic block copolymer is irradiated with active energy rays, the irradiation preferably takes place at a humidity relative not more than 30%, and more preferably not more than 10% to avoid decomposition of the (meth)acrylic block copolymer.

During or after active energy ray irradiation of the (meth)acrylic block copolymer described herein, or with the active energy ray curable composition including the (meth)acrylic block copolymer, heating may be performed as described below. required to promote curing. The heating temperature is preferably in the range of 40 to 130°C, and more preferably in the range of 50 to 100°C.

Examples of use applications for the active energy beam curable compositions of the invention include curable resins, adhesives, pressure sensitive adhesives, tapes, films, sheets, mats, sealing materials, sealants, coating materials, potting, inks, printing plate materials, vibration isolating materials, foams, heat sinks, prepregs, gaskets and fillers used in such fields as automobiles, household appliances, buildings, civil engineering, sports, displays, optical recording devices, optical equipment, semiconductors, batteries and printing.

examples

The present invention will be described in more detail based on the following examples. However, it should be understood that the scope of the invention is not limited to such examples.

In the examples, BMA, AMA, MMA, 2-EHA and BA represent 3-methyl-3-butenyl methacrylate, allyl methacrylate, methyl methacrylate, 2-ethylhexyl acrylate and butyl acrylate, respectively.

In the following examples and comparative examples, the raw materials used had been dried and purified by known methods and deaerated under nitrogen. They were transferred and fed under a nitrogen atmosphere.

Monomer consumption rate

In the examples and comparative examples described later, the consumption rate of a monomer after polymerization was calculated as follows. A 0.5 ml sample of the reaction liquid was taken and added to 0.5 ml of methanol, and these were mixed. A 0.1 ml portion of the liquid mixture was sampled and dissolved in 0.5 ml of deuterated chloroform. The solution was analyzed by 1H-NMR under the conditions described below. The consumption rate was calculated based on the change in the ratio of the integral of a peak assigned to the protons directly attached to the carbon-carbon double bond of the (meth)acrylate ester used as monomer (chemical shift 5.79-6, 37 ppm) to the integral of a peak assigned to the protons directly bound to the aromatic ring of toluene used as solvent (chemical shift 7.00-7.38 ppm).

1H-NMR measurement conditions

Apparatus: "JNM-ECX400" nuclear magnetic resonance apparatus manufactured by JEOL Ltd.

Temperature: 25°C

Number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn) A polymer obtained in the example or comparative example described later was analyzed by GPC under the following conditions to determine the molecular weight number average (Mn) and weight average molecular weight (Mw) relative to standard polystyrenes, and the molecular weight distribution (Mw/Mn) was calculated.

GPC measurement conditions

Apparatus: GPC Apparatus "HLC-8220GPC" manufactured by TOSOH CORPORATION

Separation columns: "TSKgel Super Multipore HZ-M (column diameter = 4.6 mm, column length = 15 cm)" manufactured by TOSOH CORPORATION (Two columns were connected in series).

Eluent: Tetrahydrofuran

Eluent flow rate: 0.35 ml/min

Column temperature: 40°C

Detection Method: Differential Refractive Index (RI)

Cure speed (degree of reaction)

The curing speed of an active energy ray curable composition obtained in the example or comparative example described below was evaluated with a viscosity/viscoelasticity measuring device (MARS III manufactured by HAAKE).

On parallel plates having a diameter of 20 mm, 1 g of the active energy ray curable composition obtained in the Example or Comparative Example was dropped to form a film. The measurement mode was High speed OSC time dependent measurement mode. Viscoelasticity was measured at a measurement temperature of 25°C, a measurement gap of 0.30 mm, and a measurement frequency of 1 Hz while irradiating the film with ultraviolet light from an ultraviolet lamp (Omni Cure Series 2000 manufactured by Lumen Dynamics, intensity 50 mW/cm2).

As an index of the curing rate, the degree of reaction (%) was obtained using the following equation where G' (0) was the storage shear modulus (Pa) at the start of UV application, G' ( 20) the storage shear modulus (Pa) after 20 seconds from the start of the UV application (after application of 1000 mJ/cm2), and G' (120) the storage shear modulus (Pa) saturated within 120 seconds from the start of the UV application (after the application of 6000 mJ/cm2).

Degree of reaction (%) = {G' (20) - G' (0)}/{G' (120) - G' (0)} x 100

Example 1

Stage 1)

The interior of a 3 L flask was dried and purged with nitrogen and 1.30 kg of toluene was added. While stirring the solution in the flask, 1.5 g of N,N,N',N",N"-pentamethyldiethylenetriamine as Lewis base and 20 g of a 26 mass% solution of isobutylbis(2 ,6-di-t-butyl-4-methylphenoxy)aluminum in toluene as the organoaluminum compound. The mixture was cooled to -30°C. In addition, 3.7 g of a 10 mass% solution of sec-butyllithium in cyclohexane was added as the organolithium compound, followed by the addition of a single portion of 6.9 g of a monomer mixture including 3.0 g of BMA and 3.9 g of MMA. This started the anionic polymerization. Subsequently, the reaction liquid was stirred at -30°C for 12 hours, and samples of the reaction liquid were taken.

In Stage (1), the consumption rates of BMA and MMA were 100%.

Stage 2)

Subsequently, while stirring the reaction liquid at -30°C, 445 g of 2-EHA monomer were added at a rate of 5 g/min. Immediately after the monomer addition was complete, samples of the reaction liquid were taken.

In Stage (2), the consumption rate of 2-EHA was 100%.

Stage (3)

Subsequently, while stirring the reaction liquid at -30°C, 6.0 g of a monomer mixture including 2.6 g of BMA and 3.4 g of MMA were added at once. The temperature was increased to 25°C. Samples of the reaction liquid were taken after 300 minutes from the addition of the mixture.

In Stage (3), the consumption rates of BMA and MMA were 100%.

Stage (4)

Anionic polymerization was terminated by adding 40 g of methanol while continuously stirring the reaction liquid at 25°C. Thus, a solution was obtained containing a (meth)acrylic block copolymer that was a triblock copolymer composed of a methacrylic polymer block (A), an acrylic polymer block (B) and a methacrylic polymer block (A), joined in this order (ABA ). A sample of (meth)acrylic block copolymer taken from solution had an Mn of 71,000 and an Mw/Mn of 1.03.

Stage (5)

Then, the solution obtained above was poured into 5,000 g of methanol to precipitate an oily precipitate. The oily precipitate was recovered and dried to give 420 g of the (meth)acrylic block copolymer (hereinafter, referred to as "(meth)acrylic block copolymer (1)").

Stage (6)

Next, 20 g of n-octyl acrylate as a reactive diluent and 5 g of 1-hydroxycyclohexyl phenyl ketone (IRGACURE (trademark) 184, manufactured by Ciba Specialty Chemicals) were added to 80 g of the (meth)acrylic block copolymer (1). The mixture was stirred to give a solution. Thus, 105 g of an active energy ray curable composition was obtained. The curing speed of the active energy ray curable composition was measured by the method described above, and the degree of reaction was determined to be 94.0%. The result is described in Table 2.

Example 2

A (meth)acrylic block copolymer was obtained in the same manner as in Example 1, except that the amounts of BMA, MMA, 2-EHA and BA used in Steps (1) to (3) were changed as described in Table 1. The obtained (meth)acrylic block copolymer will be referred to as (meth)acrylic block copolymer (two).

Furthermore, an active energy ray curable composition including the (meth)acrylic block copolymer (2) was obtained in the same manner as in Example 1, except that the amounts of n-octyl acrylate and 1-hydroxycyclohexylphenylketone used in the Step (6)) were changed as described in Table 2.

Comparative Examples 1 and 2

The (meth)acrylic block copolymers were obtained in the same manner as in Example 1, except that the amounts of BMA, AMA, MMA, 2-EHA and BA used in Steps (1) to (3) were changed as is described in Table 1. The (meth)acrylic block copolymers obtained in Comparative Examples 1 and 2 will be written as the (meth)acrylic block copolymers (3) and (4), respectively.

Furthermore, active energy ray curable compositions including the (meth)acrylic block copolymer (3) or (4) were obtained in the same manner as in Example 1, except that the amounts of n-octyl acrylate and 1 -hydroxycyclohexylphenylketone used in Step (6) was changed as described in Table 2.

Table 1

Table 2

As is clear from Table 2, the active energy beam curable compositions of Examples 1 and 2 achieved high cure rates where the methacrylic polymer blocks (A) contained BMA as monomer units having an energy curable group. rays of active energy with a partial structure (1). One reason for this is probably that the hydrocarbon group (the α-methyl group) represented by R 1 in the general formula (1) was an electron donor, and consequently, the active energy ray curable group achieved higher reactivity.

In contrast, the curing speed was low in the active energy beam curable compositions of Comparative Examples 1 and 2 in which the methacrylic polymer blocks (A) did not contain monomeric units having an energy beam curable group. active with a partial structure (1). One reason for this is probably that the allyl group which was the active energy ray curable group did not have an electron donating hydrocarbon group at the a-position and, consequently, the reactivity of the active energy ray curable group was low.

From the foregoing, it has been shown that the (meth)acrylic block copolymers described herein have excellent active energy ray curability, in particular, curability of blends thereof with acrylate monomers. .

The block copolymers described herein are useful as active energy beam curable compositions that are cured by irradiation with active energy rays such as UV lights or electron beams.

Claims (2)

1. An active energy ray curable composition, comprising a (meth)acrylic block copolymer comprising a methacrylic polymer block (A) having an active energy ray curable group including a partial structure (1) depicted by the general formula (1) below, and a block (B) of an acrylic polymer having no groups curable by active energy rays;

where R1 indicates a hydrocarbon group having from 1 to 10 carbon atoms, and W indicates a saturated hydrocarbon group having from 1 to 10 carbon atoms, where the methacrylic polymer block (A) having the active energy ray curable group including a partial structure (1) includes monomer units which are derived from a methacrylate ester represented by the general formula (2) below;

where R1 and W are as defined hereinbefore. 2. The active energy ray curable composition according to claim 1, wherein the ratio of the number of moles of the partial structures (1) with respect to the number of moles of all the monomeric units constituting the polymer block (A) methacrylic is 0.1 to 50 mol%.